Scant literature focuses on the determinants of carbon assurance, especially how board centrality and peer carbon assurance influence a company's decision to adopt voluntary carbon assurance. This study investigates whether directors' superior access to high-quality information through their board networks affects the likelihood of adopting voluntary carbon assurance. Meanwhile, it explores how peer carbon assurance (frequency-based imitation versus outcome-based imitation) shapes the likelihood of firms with greater board centrality to voluntarily acquire carbon assurance. This study employs firms on Taiwan and Taipei exchanges from 2016 to 2021 as the research sample. Our findings indicate that the likelihood of companies acquiring voluntary carbon assurance is positively associated with board centrality. Furthermore, this relationship is reinforced by the number of pioneering peers already reducing carbon emissions and acquiring carbon assurance. However, the association is not influenced by the number of pioneering peers' carbon assurance.